The present invention relates to a video game device. More particularly, this invention relates to a game device which is installed at amusement centers or at home and which is capable of expressing more realistic pictures.
With the progress of computer technology, video game devices utilizing computer graphics technology have come to be widely used. This type of video game devices are widely accepted by users. A large number of various kinds of game devices have been devised and various game software products which run on such game devices have been supplied.
It is desirable that pictures be displayed in more realistic expressions on a screen so that users would be able to enjoy video games fully. For example, with a vehicle race such as a car race, it is desirable that movements of cars and the background be expressed naturally and that anything which may occur during the drive, for example, reflection of light on a windshield be expressed as special effects on a screen. Moreover, it will be interesting if traces of tire slips of a car appear.
On the other hand, since complicated arithmetic operations such as coordinate transformation are repeated for three-dimensional screen display, the amount of operation borne by CPU becomes enormous. Accordingly, if special effects or the like of picture expressions are performed, the number of polygons to be displayed on the screen must be decreased by the amount of operation to be used for such special effects.
Therefore, it is a first object of this invention to provide a video game device capable of expressing a picture with which a game player can perceive dazzling light from a light source.
It is a second object of this invention to provide a game device capable of expressing, on a screen, traces of a moving object in a video game.
It is a third object of this invention to provide a method of decreasing the amount of operation in a drawing routine when developments of a game in the three-dimensional virtual space are displayed on a two-dimensional screen so that pictures on the screen may seem to be three-dimensional.